As is well known, access barriers, such as garage doors or gates enclose an area, and allow selective ingress and egress thereto. In the past, garage doors were moveable by hand, but due to their weight, and the inconvenience of opening and closing the door, motors were added to move the door between opened and closed limit positions. Control of the motor may be achieved by a hard-wired push button, which when actuated, sends a signal to a barrier operator that initiates the motor so as to move the door to one of its limit positions. After the door has stopped, and the button is pressed again, the barrier operator directs the motor to move the door in an opposite direction. In addition, to the basic motor control functions discussed, barrier operators are now provided with safety features, which stop and reverse the door travel when an obstruction is encountered. Other safety devices, such as photocells and sensors when combined with the barrier operator, detect whenever there is an obstruction within the path of the door and send a signal to the barrier operator to take corrective action. Remote control devices are now also provided to facilitate the opening and closing of the door without having to get out of the car. In addition to these basic features, the prior art also discloses various other features, which enhance the convenience of opening and closing an access barrier such as a garage door.
One feature offered by various barrier operators relates to an auto-close mode. The auto-close mode allows the barrier operator to close a currently opened access barrier without any interaction from the user or other individual. Such a feature allows a user that does not have a remote transmitter to exit an area whose access is controlled by the access barrier, while ensuring that the access barrier will close a short time later. As such, the auto-close mode of the barrier operator provides an enhanced level of security and convenience to its user. While several attempts have been made to provide a suitable auto-close feature, most attempts are lacking in one or more aspects, as discussed below.
For example, one attempt to provide a barrier operator with an auto-close mode is achieved by use of a delay-close button that is provided by a wireless wall station. When actuated, the delay-close button generates a signal received by the barrier operator which pauses for a predetermined period of time before the access barrier begins to close. Unfortunately, if a user forgets to press the delay-close button, the access barrier remains open allowing unwanted individuals to gain access to the area controlled by the access barrier.
Other barrier operator systems developed to provide an auto-close feature utilize a timing module that is configured to be added to an existing barrier operator installation. Once installed and configured, the timing module initiates a count once the access barrier is opened. If another command signal is not received by the barrier operator before the remaining time expires, then the barrier operator closes the access barrier. However, because the timing module is an add-on feature to an existing barrier operator, it may be improperly installed by an unqualified layperson. Moreover, due to the vast range of individual barrier operator models available on the market, an incompatibility may arise when the timing module is utilized therewith. As a result, the timing module may work improperly with a particular barrier operator, causing erratic and inconsistent actuation of the barrier operator.
There are also automatic controllers for barriers, such as garage doors, that are referred to as “hands-free” devices where the proximity of the mobile unit, in a car, to the stationary unit, in the garage, will open and close the barrier based on a number of conditions. One such device provides an automatic barrier operator system for operating a gate or upward acting garage door which includes a controller for operating a reversible motor, a base radio frequency transmitter and a base radio frequency receiver. One or more remote control units include a radio frequency remote receiver and remote transmitter. The controller is operable to automatically close or open the barrier in response to a query signal sent from the base transmitter to the remote receiver and when the remote receiver is within range, returning a signal to effect movement of the barrier. The system is operable to effect operation or maintain the status quo of the barrier depending on the state of the barrier and a particular signal or lack of signal received by the controller from an authorized remote control unit or units. The system provides essentially hands-free automatic operation of opening and closing a garage door and the like. Although these devices normally move the barrier from a non-user initiated command, there are no provisions to close the barrier after a period of time if for some reason the controller leaves the barrier in the open position.
Therefore, there is a need for a system and method for unattended control of an access barrier that provides a barrier operator that performs a timing function. In addition, there is a need for a system for unattended control of an access barrier that utilizes a remote transmitter or wall station which sends an auto-close signal to the barrier operator automatically, without being initiated by a user. Still yet, there is a need for a system for unattended control of an access barrier, wherein the auto-close signal sent by the remote transmitter, or wall station is sent periodically.